[Bug 625798] Re: Don't use int constants with a long data type.

[Thierry Carrez]

** Changed in: tickcount (Ubuntu)
       Status: Triaged => In Progress

** Changed in: tickcount (Ubuntu)
     Assignee: (unassigned) => Thierry Carrez (ttx)

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Don't use int constants with a long data type.
https://bugs.launchpad.net/bugs/625798
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Status in Tickcount Python Extension: New
Status in “tickcount” package in Ubuntu: In Progress

Bug description:
A debug session in #ubuntu-devel initiated by Emmet Hikory for the cause of the FTBFS for powerpc, revealing a but in the tickcount code.

tickcount's C code uses "long" for the variables but uses UINT_MAX for the wrap-around computation. The same applies to the test suite for it, it also uses UINT_MAX. This works for 32bit because sizeof(int)==4==sizeof(long) but not for 64bit where sizeof(int)==4!=8==sizeof(long). Therefore on 64bit the computation is wrong and the test suite doesn't check a wrap around (as the values used fit into 64bit and no wrap-around happens).